McLaren team principal Martin Whitmarsh believes Lewis Hamilton already has some regrets over his move to Mercedes.

Whitmarsh concedes he still does "not fully understand" why Hamilton opted to quit McLaren after 14 years and join Mercedes, who have won just one race in three years since their return to Formula One.

Whitmarsh can appreciate Hamilton's desire "to flee the nest" but remains disappointed by his decision, in particular as he feels it was made after a bad result in Singapore.

That was a race Hamilton should have won to firmly thrust himself back into the title picture, only to retire on lap 23 with a gearbox failure.

"It is always bad to make a decision in the aftermath of a bad race," Whitmarsh told the official F1 website.

"He was pretty sure he was going to win that race and it (the retirement) was a disappointment.

"I respect his decision, but I believe he would be better off with us; we are the stronger team and we intend to beat him next year."

Since Hamilton announced he was off to join Mercedes on a £45million three-year contract, the Brackley-based outfit have failed to score a single point.

McLaren have hardly set the world on fire either, although Hamilton should have won in Abu Dhabi on Sunday only to suffer another mechanical issue while leading from pole position.